A Systematic Approach to Enable Mask Respin in OPC Flows
Publication Date: 2017-Apr-06
The IP.com Prior Art Database
Disclosed is a systematic approach to enable mask respin in OPC flows.
Title A Systematic Approach to Enable Mask Respin in OPC Flows Abstract Disclosed is a systematic approach to enable mask respin in OPC flows. Problem Back-end-of-line (BEOL) layers are interdependent in terms of retargeting and optical proximity correction (OPC). If a manufacturer receives BEOL respin requests from a customer, then the manufacturer must determine how it affects the layers above/below the layers that need respin. Figure 1: Respin concept: Customer decides to change the design of some BEOL layers, Li till Ln, etc.
Figure 2: BEOL layers are interdependent
Via retargeting is based on upper/lower metal targets Metal layers have coverage/enclosure optical rule check (ORC) of via layers Via layers have bridging checks to metal layers
Figure 3: Other layers respin Li-1, Ln+1?
To answer this question, a method is needed to:
Run special ORC tech files mixing AZ & BZ inputs Establish logical xor operation (XOR) for old mask (AZ) and new mask (BZ) table
driven layer operation (TDLO) layouts Each BEOL ORC tech file should have two extra variables that are set to 0 by default.
RESPIN_LB re-spin layer below RESPIN_LA re-spin layer above
If any of these variable is set to 1, then the corresponding TDLO required layers are passed to ORC. This is not to be confused with metal layers reading below via layers Figure 4: ORC to enable re-spin
No solid methodology is available for determining whether the manufacturer needs to respin layers above/below. The following needs to change:
Same engineering change notice/engineering change notice (ECN/TECN) used for AZ should be used...